Owner's Manual

16
Total Protection - Relays
Each channel of the A 52+ has a high-quality protection relay with gold-plated contacts
for long-term reliability. These relays function to protect either the amplifier, the speakers, or
both. When the A 52+ is first powered on, these relays remain open for three seconds as the
positive and negative power supplies stabilize and reach equilibrium. This prevents annoying
popping or other transient noises. Relay protection also prevents damage to your speakers in
case of a catastrophic amplifier failure. Any amplifier that doesn’t use relay protection for its
speaker outputs compromises the safety of the amplifier and your speakers.
Total Protection - Current Overload
Specialized current-sensing transistors are connected to the output stages of the A 52+
to constantly monitor the current flow through the output transistors. If the current drawn by
this stage exceeds a predetermined safe level due to a load impedance below 1 ohm or a
short circuit at the speaker terminals, the output relay will open immediately to prevent the
output transistors or other parts from failing.
Total Protection - Fuses
Each channel of the amplifier has two fuses for its positive and negative DC voltage
rails. These fuses provide backup protection in case the over-current protection does not work
in time, or if an internal part fails. In the event of a part failure, these fuses halt operation to
minimize damage to additional parts.